The present invention relates to a visible display card including a printing layer in which images such as characters and patterns can be printed by heat treatment, and an IC which can perform input/output via external terminals. The invention also relates to a card processing system using the card.
In the past, cards such as cash cards having a magnetic strip have been widely used. In recent years, cards occasionally called IC cards which contain an IC or an embedded IC chip with a magnetic strip so as to increase the recorded data volume have been used. FIG. 9A shows an example of such a card, and numeral 2a refers to an external terminal of an IC contained in the card and numeral 3 refers to a magnetic strip.
Recently, rewritable cards in which the previous image is erased and only the newest image is printed at the same position as the previous image are available. The rewritable card is manufactured of a resin substrate and a rewritable layer which is made of a heat-reversible recording material and is laminated on the substrate. A thermal head unit of a card processing unit performs heating/cooling processes on the rewritable layer according to the characteristics thereof so as to repeatedly perform erasing/printing, in other words, rewriting images. The inventors have been performing research on cards which have the functions of such a rewritable card with the above-mentioned IC card. FIG. 9B shows an example of such a card, in which external terminals 2a of an IC and a rewritable layer 1 are provided at the surface of the card, and a magnetic strip 3 is provided on the reverse surface thereof.
Positions and heights of external terminals of ICs are regulated according to xe2x80x9cJapanese Industrial Standard No. 6303xe2x80x9d. As shown in FIG. 9B, the distance L between the edge of the card and the farthest external terminal 2a from the edge is 28.55 mm or more. The height of the external terminal 2a is regulated to withinxc2x10.1 mm from the surface of the card. Typically, the height is determined so as to project the external terminal 2a within 0.1 mm from the surface of the card in order to ensure contact between the external terminals and the terminals of the IC unit.
In the meantime, there is a strong demand to expand the printing area by enlarging the width of the rewritable layer 1. If the width of the rewritable layer 1 is enlarged, the rewritable layer 1 adjoins the end external terminal 2a. However, the length of the erasing head H is set to be longer than the width of the rewritable layer 1 in order to ensure proper erasing, and the erasing head H may be arranged so as to overlap the end thereof with the external terminal 2a. As a result, erasing head H contacts the external terminal 2a, and external terminal 2a and the internal circuit of the card may be damaged by heat, and the erasing of the image is not properly performed due to poor contact between the erasing head H and the rewritable layer 1. This problem is not limited to rewritable cards, but is generally found in all IC cards on which thermal printing is performed.
The present invention has been completed in view of the above circumstances. An object of the invention is to provide a visible display card and a card processing system in which the thermal head does not contact the external terminal, whereby the printing layer can be as wide as possible.
The present invention provides a visible display comprising a printing layer provided on at least one side of the card, and an IC disposed by the side of the printing layer and having an external terminal. The printing layer is printable thereon by being heated, and the height of the printing layer from the surface of the card is greater than that of the external terminal.
According to the visible display card, even if the end of the thermal head is disposed to overlap the external terminal, the thermal head contacts the printing layer without contacting the external terminal, since the height of the printing layer above the surface of the card is greater than that of the external terminal. More specifically, the card is rectangular in plan view, and the printing layer extends along the longitudinal direction of the card as a strip. The thermal head contacts the printing layer and relatively moves toward longitudinal direction thereof. During the procedure, the end of the thermal head passes over the external terminal. Thus, the visible display card of the invention enables enlargement of the width of the printing layer so as to be wide as possible, preventing contact between the thermal head and the external terminal.
The IC may be contained in the card, and the external terminal is exposed at the surface of the card. Alternatively, the card has the IC embedded therein, and the external terminal is exposed at the surface of the IC. A magnetic strip may be provided on at least one side the card. Moreover, the printing layer may adjoin the IC in the longitudinal direction of the card. Alternatively, the printing layer may adjoin the IC in the longitudinal direction of the card and the direction perpendicular to the longitudinal direction.
The present invention also provides a card processing system using the above visible display card and a card processing unit. The card processing unit comprises a thermal head which is movable so as to contact and separate from the printing layer of the card traveled in the unit, and forms images on the printing layer by contacting and heating the printing layer, and an IC unit having a terminal for contacting the external terminal of the IC. A card processing system so constructed allows the width of the printing layer to be enlarged so as to be as wide as possible, preventing contact of the thermal head and the external terminal.
The thermal head may be arranged so that the end thereof overlaps the external terminal of the IC in plan view. The thermal head may comprise a head for printing images on the printing layer and a head for erasing images printed on the printing layer.